1995 K1500 Loud Ticking After Exhaust Manifold Replacement

This is a discussion on 1995 K1500 Loud Ticking After Exhaust Manifold Replacement within the Technical / Maintenance forums, part of the General Discussion category; Hey everyone, I'm new here and I decided to register as I now own a '95 K1500 Z71 and found ...

1995 K1500 Loud Ticking After Exhaust Manifold Replacement

Hey everyone, I'm new here and I decided to register as I now own a '95 K1500 Z71 and found this forum extremely helpful thus far. Anyways, my dad and I replaced the left (driver side) exhaust manifold and now there is an EXTREMELY loud ticking noise coming from the left side when I give the truck any gas. We also noticed that when we took the old manifold off there was no gasket on it, which we replaced with gaskets provided with the Dorman manifold.
My question is this: What is causing this extremely loud ticking noise when I give the truck any gas? Did we position the gasket incorrectly when we put the new manifold on? Is a spark plug perhaps loose?
I apologize if this subject has been beaten to death. I did try to search but did not find anything relating to my exact issue.
Any help is much, much appreciated.

Re: 1995 K1500 Loud Ticking After Exhaust Manifold Replacement

It probably took you longer to post this question than it would have to check the spark plugs.

If this randomly happened while driving to someone who never pops the hood. We can throw alot of guesses at your problem but since you managed a manifold replacement. You are obviously comfortable under you hood.

You have an exhaust leak. Even the manifold to exhaust can have a ticking sound. Torque the bolts again and listen for a change ticking sound.

Re: 1995 K1500 Loud Ticking After Exhaust Manifold Replacement

It's a little too late to get under the hood and I was throwing ideas out for clarification on what my potential problem might be.
So you're saying to retorque the bolts on the manifold, right? I went back and checked all of the bolts on the manifold and where the "donut" gasket is and none of them are loose, which is why I am puzzled.

Re: 1995 K1500 Loud Ticking After Exhaust Manifold Replacement

You have a leak somewhere. Put a straight edge across the manifold and make sure it's straight and do the same on the head. You should see black where it's leaking if its that bad. These are for headers but will seal unless something is warped real bad. http://www.summitracing.com/parts/PHP-66121/

Re: 1995 K1500 Loud Ticking After Exhaust Manifold Replacement

If they seem tight check the plugs. Also how did you tighten the manifolds? just a ratchet or torque wrench

I tightened them with a ratchet at first so the manifold would hold and then went back to snug them with a torque wrench. I checked again today and none of them were loose.

Bowtie44s - I will try that tomorrow morning. Would you recommend I use those header gaskets that you posted instead of the gaskets that came with the Dorman manifold? If so, do you know of any similar quality gaskets that I could pick up at, say, O'Reilly or Autozone?

Re: 1995 K1500 Loud Ticking After Exhaust Manifold Replacement

I tightened them with a ratchet at first so the manifold would hold and then went back to snug them with a torque wrench. I checked again today and none of them were loose.

Bowtie44s - I will try that tomorrow morning. Would you recommend I use those header gaskets that you posted instead of the gaskets that came with the Dorman manifold? If so, do you know of any similar quality gaskets that I could pick up at, say, O'Reilly or Autozone?

My autozone has them for a 350. If there is a slight imperfection those gaskets will seal a lot better, they are thicker, like 3 layers and softer. I would check to see if there is a bur or something behind them holding them up and the straight edge check. Manifolds rarely leak. Make sure it is leaking there. A leak as loud as you described should be easy to feel with your hand at idle.

Re: 1995 K1500 Loud Ticking After Exhaust Manifold Replacement

Did you replace the donut, too? I would do the donuts on both sides if you find out it's leaking on your ticking side. Mine was - it's tough to see or feel but I found it to be the source of the ticking. It was most obvious at first start-up + when I stomped on it in gear. The best way in my opinion is to drop the exhaust off the hangers so it is free floating (close to the installed position as possible) - replace donuts with new bolts/hardware and re-hang the exhaust.

Re: 1995 K1500 Loud Ticking After Exhaust Manifold Replacement

-Bad manifold. Was it used, aftermarket? They needed to be check for flatness before installing. My used ones were extremely warped and managed to score some almost NOS GM ones.

-Gasket. GM did not use a gasket from the factory. My new bolts loosened up last week allowing the gasket to slide up (i had the gaskets with hooks). I'm wondering if I should've not used them now.

- Donut gasket to pipe. These crush on installation and must be replaced. I had lots of trouble getting mine to seal up right, with the springs on the bolts it only applies so much pressure to crush these gaskets. My y pipe was not a perfect fit and I had to add some washers to get it to seal.

You can use a piece of hose (fuel line etc.) in your hear to listen around and pinpoint the leak.

Re: 1995 K1500 Loud Ticking After Exhaust Manifold Replacement

Bowtie44s - This may seem like a stupid question: Do you even need to install a gasket for the exhaust manifold? The reason I ask is because after I took the left (driver side) exhaust manifold off there was no gasket and it seems that this loud ticking noise began AFTER I installed a gasket on the manifold. I thought you always had to install a gasket between the block and the exhaust manifold, however, as I previously stated, there was no gasket on the old manifold I removed. The gaskets that came with the Dorman manifold seemed flimsy, so perhaps I should buy a better set of gaskets.

Montana3/4ton - I did replace the "donut" gasket when I replaced the left (driver side) manifold. I have the manifold for the right side, but I just haven't had the time to install it. I even went back, unbolted everything, checked the "donut" gasket, and then retightened the three bolts where the gasket is.

Jayrodoh - The manifold is a brand new Dorman. I used the gaskets that came with the Dorman manifold, which also had "hooks" like the ones you described. Should I pick up some hook-less gaskets or buy some better quality gaskets with the "hooks"? As for the "donut" gasket, I also replaced that with a brand new one that came with the manifold. I even went back, unbolted the three bolts, took the "donut" out, reinstalled the "donut" and then bolted everything back together.

Re: 1995 K1500 Loud Ticking After Exhaust Manifold Replacement

Someone else said gm didn't use gaskets. Maybe you're ahead not to. I really only mess with headers. I have taken off manifolds and they had gaskets but i've never installed manifolds. You could try it without and see but if you do need gaskets i highly recommend those aluminum ones. I have also heard to just use a bead of ultra high temp copper rtv and that is the best you can get. Once again, all my information is for headers.

Re: 1995 K1500 Loud Ticking After Exhaust Manifold Replacement

Jayrodoh - If I absolutely have to I will take everything off again and double check to make sure the manifold is flat. I'm pretty sure it was when I was examining and comparing it to the old one, but mistakes do happen. As far as removing the gaskets, can I simply loosen the bolts on the manifold itself or do I have to go through the pain of removing the power steering pulley again to get that damn bracket out of the way?

Bowtie44s - I understand what you're saying. My plan was to remove the gasket and then check for noise and if it persists, buy another gasket and see if that solves the problem. I'll see if I have time today to get under the hood and then I'll post an update regarding the situation.

Re: 1995 K1500 Loud Ticking After Exhaust Manifold Replacement

2- things you need to do. 1- put a gasket on the manifold. You can buy them at autozone. They are 3 or 4 gaskets on one side. 2-put permatex ultra gold copper on the donut gasket and tighten. Wait a day and let dry then run the truck.

Re: 1995 K1500 Loud Ticking After Exhaust Manifold Replacement

I loosened the manifold yesterday and removed the gasket that I installed with the new Dorman manifold. Started it up and no more ticking. I opened the box that is holding my other brand new manifold and noticed a small slip of paper that states, "FOR OPTIMUM SEALING... THE VEHICLE MANUFACTURER RECOMMENDS NOT USING A HEAD-TO-MANIFOLD GASKET FOR THIS APPLICATION." What the hell is that about? I cross-referenced the information provided on the slip with the information in a Haynes repair manual I have and the repair manual states a gasket should be installed with the exhaust manifold. I don't understand why there is so much conflicting information regarding whether to install a gasket or not.